The operation of a crane requires periodic replacement of the cable, wire, rope, or any other flexible line that is wound on a crane winch spool. Although the use of cranes is commonplace, proper cable storage and installation procedures are less well known. As kinks, binding, or uneven winding can damage or seriously weaken the cable, proper cable storage and installation techniques must be followed to avoid damaging the cable.
Therefore, to maximize the life of a cable and to insure proper installation, the cable must be wound onto the cable spool tightly, under proper tension. Loose windings and spaces between windings are undesirable and each layer must be completed before the next layer is started. Any space between windings may permit the overriding layer to fall down to a lower layer and become jammed or wedged between the lower windings. A cable jammed in such a manner is easily frayed, kinked, or damaged.
Proper cable installation is typically accomplished utilizing manually operated tensioning devices. For example, the cable needs to be extended and a load placed at the end of the cable in order to assure that the cable is tight and tracking properly on a spool. To accomplish this, the cable is typically first unwound from a new cable spool and, then, the end of the cable is secured to a load or an immovable object. Thereafter, the crane or the load, attached thereto, is backed away until tension is introduced into the cable. Next, the crane winch spool is turned to wind the cable thereon, while the cable remains under tension due to the mass of the crane or the friction of pulled load against the ground. As the cable is wound onto the spool, tension is retained in the cable windings.
Several problems are associated with the above procedure. One problem is that, as the cable is laid out on the ground, sand or earth particles can be caught between threads of the cable. Such debris acts as an abrasive within the cable and weakens the cable over time. Another problem is the inability to precisely and repeatedly introduce proper tension into the cable, due to the resistance between the load and the crane not being precisely controlled as the cable is wound onto the winch spool.
Devices have been developed to improve and simplify the process of installing cable onto a crane. Other devices have been developed to apply tension to cable as it is wound onto a spool. Although, some devices include various mechanisms to distribute cable evenly and under tension, they are still needlessly complex and incapable of being used with existing cranes. Some devices include a series of sheaves, which resist rotation, thereby creating tension in the cable as it is fed therethrough and wound onto a winch spool. Some devices incorporate bars or plates that ride against the cable windings to hold the cable down against the spool and prevent the cable from coming loose. These bars or plates are biased against the spool with springs or similar mechanisms. Although the bars and plates hold the cable against the spool, these devices do not accurately maintain tension in the cable or ensure that the cable is wound evenly and tightly on the spool. In yet other devices, the cable is fed through traction rollers, which resist rotation, wherein the traction rollers rub against the cable as it is wound onto or from a spool.
There is a need for a simple device that introduces tension into a cable as it is wound onto a winch spool. There is a need for a cable-installing device that is compact and requires minimal space during operation. There is a need for a cable-installing device usable with a stationary or a mobile crane, wherein the device can be operated by a single person to properly and quickly install cable onto a crane spool. There is a need for a cable-installing device that is compact, portable, and can be easily assembled and disassembled.